SELF-CLEANING ROTATING SIGHT GLAS AND CENTRIFUGE MACHINE HAVING SAID ROTATING SIGHT GLASS

Description

Field of the Art

[0001] The present invention relates to the field of self-cleaning rotary viewing holes and to a centrifugal machine provided with a rotary viewing hole. A wide range of chemical products are used in centrifugation processes. These chemical products are driven outward due to the rotation and speed of the centrifuges, dirtying the glass panes of the viewing holes and making the viewing of the process difficult.

[0002] The rotary viewing hole of this invention is provided with a transparent rotary panel located inside the centrifugal machine, connected to a motor causing the rotation thereof. The glass panel rotational speed prevents the adherence of splashes of chemical products, chemical product particles or droplets and the visibility is perfect throughout the entire centrifugation process.

State of the Art

[0003] Self-cleaning rotary viewing holes known in the field of the art consist of a transparent circular panel connected to a rotary frame and to a motor causing the rotation thereof, which pushes out any impurity that may be deposited on its surface, keeping the viewing hole free of impurities and therefore maintaining its visibility.

[0004] Rotary viewing holes of this type are known particularly in the field of watercrafts, where the windows of the navigation bridge of the watercraft are usually equipped with rotary viewing holes for maintaining visibility even in rainy or stormy conditions, said rotary viewing holes being free of water and therefore maintaining a much greater visibility than the rest of the windows of the navigation bridge.
Thus, DE 3407612 A1 discloses a circular viewing hole for the control cabin of boats and the like., including a stationary frame (2) with a transparent panel (8), a rotary frame (21) connected to said stationary frame (2) by means of a rotary joint and a transparent panel (18) attached to said rotary frame (21) by means of a joint, an intermediate chamber separating said transparent panels (21) and (18) facing each other and a motor being connected to said rotary frame. According to figures 5 to 7 that are cross sections throughout different portions of the annular frames, it can be seen that rotary frame (21) defines a cavity to receive the transparent panel (18), the cavity being delimited by a conical wall extending towards the intermediate chamber and holding the transparent panel (18) in place.

[0005] The use of rotary viewing holes of this type in machine tools is also known through patent document DE102008045793A1, for example.

[0006] Patent document DE102010061587A1 also describes a rotary viewing hole, in this case provided with a particular construction for rotatably operating the rotary glass pane.

[0007] None of the known background documents describes a solution which allows leak-tight fixing of the rotary glass pane to the rotary frame containing it with a precise centering that prevents vibrations and without using adhesives that may deteriorate upon contact with solvents and become detached over time. There is also no knowledge of anyone having provided an inertization system for any of the mentioned viewing holes which allows using them in potentially explosive atmospheres and allows them to be ATEX standard-compliant and ATEX-certified, i.e., providing in the viewing hole means for preventing the entry of oxygen and any other product from the outside which may cause an explosion.

Brief Description of the Invention

[0008] The present invention relates to a self-cleaning rotary viewing hole for a centrifugal machine and a centrifugal machine according to the appended claims.

[0009] It will be understood that a centrifugal machine is a machine provided for mechanically separating a solid and a liquid, or for separating particles suspended in a liquid by means of highspeed centrifugation. A typical example of centrifuges of this type consists of machines intended for separating active ingredients resulting from a precipitate or crystallization before a chemical reaction.

[0010] In this case, the proposed rotary viewing hole includes:

• a stationary frame;
• a transparent stationary panel or glass pane attached to said stationary frame by means of a leak-tight joint;
• a transparent rotary panel or glass pane, integral with a rotary outer frame, attached, at the center, for example, to a motor with a coupling fixing and drive system, said transparent rotary panel being arranged opposite and spaced apart from the transparent stationary panel by means of an intermediate chamber;
• a motor connected to said transparent rotary panel or glass pane or to said frame to cause the rotation thereof with respect to the stationary frame about a central axis of rotation perpendicular to said transparent rotary panel, a rotary joint having been provided between the rotary frame and the stationary frame.

[0011] In other words, the transparent rotary panel and the rotary frame are attached forming a first assembly which, when operated by a motor, rotates with respect to a second assembly formed by the stationary frame and the transparent stationary panel, both first and second assemblies being connected through the mentioned rotary joint.

[0012] It will be understood that both the transparent rotary panel and the transparent stationary panel could be made from any transparent material, such as, for example, glass, methacrylate or another transparent plastic compatible with the inner atmosphere of the machine or processing equipment to be isolated or confined.

[0013] The present invention proposes that the attachment between the transparent rotary panel and the rotary frame be an interference attachment between a transparent rotary panel perimetral face and a rotary frame coupling facefacing said transparent rotary panel perimetral face, the transparent rotary panel being fitted into the rotary frame.

[0014] It will be understood that an interference joint attached by means of a dimensional interference fit is a fit produced when the transparent rotary panel has a size larger than the cavity defined by said rotary frame coupling face before the coupling thereof, such that after coupling, the transparent rotary panel is compressed by the rotary frame, and said rotary frame is elastically pulled all around, assuring a secure and leak-tight attachment without requiring the use of adhesives.

[0015] To achieve said dimensional interference fit between the transparent rotary panel and the rotary frame, it is proposed to heat the perimetral frame, causing it to expand, and cool the transparent rotary panel, causing it to shrink, which thereby allows introducing the transparent rotary panel into the cavity defined by the rotary frame coupling face, leaving a clearance between both which will disappear when the two elements reach one and the same temperature, the transparent rotary panel being snap-fitted into the rotary frame.

[0016] It will be understood that the transparent rotary panel perimetral face is that face or faces of the transparent rotary panel connecting its two opposite main faces.

[0017] This proposed solution allows assuring a perfect centering between the rotary frame and the transparent rotary panel as there is no space to be filled with adhesive which may allow an off-center adhesion of the transparent rotary panel with respect to the rotary frame.

[0018] Furthermore, since the proposed solution lacks adhesive, it prevents the deterioration of said adhesive from being able to lead to the release of the transparent rotary panel, causing a possible accident. Another additional advantage of the proposal is that it allows using said rotary viewing hole in contact with environments in which various solvent or corrosive agents or chemical products that may degrade said adhesive are present (like what occurs inside a centrifuge).

[0019] According to an additional embodiment, it is proposed for the transparent rotary panel to be circular. In such case, it is proposed for the transparent rotary panel perimetral face and the rotary frame coupling face to be both cylindrical and concentric with said axis of rotation. This assures that both faces are arranged opposite one another such that the compressive force of the transparent rotary panel described above is uniformly distributed and keeps the transparent rotary panel in place. Preferably, the transparent rotary panel perimetral face and the rotary frame coupling face are rectified, i.e., they have been worked with machine tools until obtaining precise dimensions within established tolerances. This allows assuring that their dimensions are the required dimensions according to the diameter.

[0020] It is further proposed for the rotary joint to be a labyrinth seal. This allows smooth, frictionless rotation between the rotary frame and the stationary frame.

[0021] The intermediate chamber contains a modified atmosphere supplied by a nitrogen line connected to said intermediate chamber when the products are processed with a solvent. Said modified atmosphere supply device can also be treated air (when not working with solvents). A positive pressure inside the viewing hole prevents the passage of air, gases, fluids or particles towards the intermediate chamber. Excess gas from inside the intermediate chamber is released through the labyrinth seal, contributing to maintaining the inert atmosphere inside the centrifuge.

[0022] The stationary frame is attached to the machine by means of screws from the outside and a leak-tight joint to a casing or manifold, the transparent rotary panel being in contact with the inside of said manifold of the machine. By way of example, said chamber can be the inside of a centrifuge, which thereby allows observing the inside of a centrifuge basket from the outside during the entire batch or centrifugation process.

[0023] The inside of the equipment can be configured for treating fluid solvents, i.e., it can include a duct for supplying solvents into said fluid treatment chamber, said solvents being used in the process. In this case, the vapors released by the solvents or the direct contact between said solvents and an adhesive may degrade the mentioned adhesive, so not using adhesives for fixing the transparent rotary panel is particularly beneficial and relevant in this case.

[0024] It is further proposed for the inside of the equipment where the rotary viewing hole is mounted to contain a modified atmosphere which is inert as a result of an inertization system, provided by an oxygen-free atmosphere, for example.

[0025] Given that the intermediate chamber of the rotary viewing hole contains, as indicated, a modified atmosphere and a positive pressure from inside to outside through the labyrinth, there can be no leaks towards the inside.

[0026] An important point lies in the fact that the modified atmosphere contained in the intermediate chamber will be at a pressure greater than the pressure of the modified atmosphere contained in the fluid treatment chamber, thereby assuring that any possible leaks through the rotary joint will always occur from the intermediate chamber to the fluid treatment chamber, thereby preventing the entry of products from the centrifuge.

[0027] It is also proposed for the stationary frame to be divided into a first stationary frame, intended for being anchored to the centrifugal machine by means of a leak-tight joint and for being connected to the rotary frame through the rotary joint, and a second stationary frame attached to the transparent stationary panel through a leak-tight joint. This configuration allows removing the rotary viewing hole assembly like a cartridge for intermediate chamber and transparent rotary panel cleaning, maintenance or inspection tasks.

[0028] According to a second aspect, the present invention relates to a centrifugal machine provided with a self-cleaning rotary viewing hole, wherein it is proposed for the mentioned rotary viewing hole to include all the features described above.

[0029] It will also be understood that the end values of any offered range of values may not be optimum and this range of values may require adaptations of the invention so that said end values are applicable, said adaptations being within the reach of a person skilled in the art.

[0030] Other features of the invention will be described in the following detailed description of an embodiment.

Brief Description of the Drawings

[0031] The foregoing and other advantages and features will be better understood based on the following detailed description of an embodiment in reference to the attached drawings which must be interpreted in an illustrative and non-limiting manner, in which:

Figure 1 shows a perspective view of the proposed rotary viewing hole, seen from the side of its transparent stationary panel, and anchored to a casing portion of a centrifugal machine, shown herein in a simplified manner in the form of a ring;

Figure 2 shows an exploded view of the rotary viewing hole shown in Figure 1;

Figure 3 shows a cross-section along the axis of the rotary viewing hole, said viewing hole being connected to the casing of a centrifugal machine provided with a fluid treatment chamber schematically shown in a simplified manner.

Detailed Description of an Embodiment

[0032] The attached drawings show an illustrative and non-limiting embodiment of the present invention.

[0033] According to that embodiment, the proposed self-cleaning rotary viewing hole for a centrifugal machine consists of a stationary frame 10 formed by a first annular stationary frame 10a and a second annular stationary frame 10b superimposed on one another.

[0034] The first annular stationary frame 10a is intended for being fixed around an opening in the casing 50 of a centrifugal machine provided with a fluid treatment chamber 51 by means of a leak-tight joint 41, for example, in the form of one or two elastic rings pressed between said first stationary frame 10 and the casing 50 of the centrifugal machine, the first stationary frame 10a being fixed by means of screws. Preferably, the screws will be placed outside the area demarcated by said elastic rings, thereby assuring that the screws do not lead to the leak-tight joint 41 breaking.

[0035] The second stationary frame 10b consists of two halves which, when attached, define an annular channel in which the perimeter of a circular transparent stationary panel 11 is fitted. The attachment between the transparent stationary panel 11 and the second stationary frame 10b also consists of a leak-tight joint 41, for example, in the form of one or two elastic rings pressed between said second stationary frame 10b and the transparent stationary panel 11. Several screws fix said second stationary frame 10b to the first stationary frame 10a in a leak-tight manner by means of a leak-tight joint 41 in the form of an elastic ring.

[0036] Each of said leak-tight joints 41 will preferably include said elastic ring inserted into an annular groove provided for such purpose.

[0037] The rotary viewing hole further includes an annular rotary frame 20 connected to said first annular stationary frame 10a through a rotary joint 40.

[0038] Said rotary joint 40 consists of a labyrinth 42, in the form of a plurality of lubrication-free circular channels in which a plurality of circular flanges are fitted, thereby guiding a rotational movement of the rotary frame 20 while at the same time making the passage of fluids and gases through said rotary joint 40 difficult as a result of the labyrinthine configuration of the labyrinth seal 42.

[0039] The rotary frame 20 is in turn connected to a flat, circular transparent rotary panel 21 through an interference joint 43. Said interference joint 43 is made up of a circular stepped recess in the entire inner perimeter of the rotary frame, defining a cylindrical-shaped rotary frame coupling face 23, said rotary frame coupling face 23 being arranged opposite an also cylindrical transparent rotary panel perimetral face 22.

[0040] The transparent rotary panel 21 and the rotary frame 20 have been rectified by means of cutting and/or polishing tools until the outer diameter of the transparent rotary panel 21, defined by said transparent rotary panel perimetral face 22, is slightly greater than the inner diameter of the cavity defined by the rotary frame coupling face 23 before coupling and at room temperature. The rotary frame 20 is then heated, causing it to expand, and the transparent rotary panel 21 is cooled, causing it to shrink, thereby allowing the transparent rotary panel 21 to be loosely inserted into the cavity defined by the rotary frame coupling face 23. The subsequent thermal equalization will cause the rotary frame 20 to shrink and the transparent rotary panel 21 to expand, the transparent rotary panel 21 thus being fitted into and pressed by the rotary frame 20, producing hermetic sealing between both without requiring the use of any kind of adhesives.

[0041] The transparent rotary panel 21 and the transparent stationary panel 11 are arranged parallel to and spaced apart from one another by an intermediate chamber 1.

[0042] To cause the rotation of the transparent rotary panel 21, it is proposed to include a motor 30, for example, a pneumatic motor, connected to said transparent rotary panel 21. In the present embodiment, the motor 30 is arranged at least partially outside the intermediate chamber 1, and going through the transparent stationary panel 11 through a circular central opening by means of a stationary connector 31, with a leak-tight joint 41 such as those described above formed by annular elastic joints, said motor being fixed to said circular central opening.

[0043] In this embodiment, said stationary connector 31 consists of a first stationary connector 31a arranged inside the intermediate chamber 1 and linked to the first stationary frame 10a by means of two radial arms 32, and a second stationary connector 31b screwed on the first stationary connector 10a from outside the intermediate chamber 1 through said central opening of the transparent stationary panel 11, the motor 30 being supported and centered by means of said stationary connector 31.

[0044] A rotor shaft which is connected to the center of the transparent rotary panel 21 projects from the end of the motor 30, such that the operation of the motor 30 causes rotation of its rotor shaft and the resulting rotation of the transparent rotary panel 21 together with its corresponding rotary frame 20. It is proposed for said connection with the transparent rotary panel 21 to be done by means of a rotary connector 33, with a leak-tight joint 41 such as those described above formed by annular elastic joints, being fixed to a circular central opening of the transparent rotary panel 21. Said rotary connector 33 can consist of a first rotary connector 33a arranged inside the intermediate chamber 1 and centered with respect to the circular central opening, attached to a second rotary connector 33b arranged on the opposite side of the transparent rotary panel 21 and attached to the first rotary connector 33a through said central opening of the transparent rotary panel 21, for example, by means of a thread. In such case, the direction of rotation of the transparent rotary panel and the direction for loosening said threaded attachment will be opposite directions.

[0045] It is further proposed to include a conduit 60 in connection with a modified atmosphere supply device and with said intermediate chamber 1, such that it allows introducing a modified atmosphere inside the intermediate chamber 1, preferably an inert atmosphere, such as a pressurized nitrogen atmosphere, to prevent the entry of oxygen and any other product from the outside which may cause an explosion.

[0046] The proposed rotary viewing hole is anchored to the casing 50 of a centrifugal machine provided with a fluid treatment chamber 51, in this case a centrifugation treatment chamber. Said fluid treatment chamber 51 will also contain a modified atmosphere supplied through ducts from said modified atmosphere supply device, preferably at a pressure less than the pressure of the modified atmosphere contained in the intermediate chamber of the rotary viewing hole.

[0047] The modified atmosphere contained inside the intermediate chamber will leak little by little through the labyrinth 42 into the fluid treatment chamber 51, preventing the fluid treatment chamber 51 from contaminating the inside of the intermediate chamber 1.

Claims

1. A self-cleaning rotary viewing hole for a centrifugal machine including:

- a stationary frame (10);

- a transparent stationary panel (11) attached to said stationary frame by means of a leak-tight joint (41);

- a rotary frame (20) connected to said stationary frame (10) by means of a rotary joint (40);

- a transparent rotary panel (21) attached to said rotary frame (20) by means of a joint, said transparent rotary panel (21) being arranged opposite and spaced apart from the transparent stationary panel (11) by an intermediate chamber (1); and

- a motor (30) connected to said transparent rotary panel (21) or to said rotary frame (20) to cause the rotation thereof with respect to the stationary frame (10) about an axis of rotation perpendicular to said transparent rotary panel (21);

wherein the joint between the transparent rotary panel (21) and the rotary frame (20) is an interference attachment (43) obtained by a dimensional interference fit produced between a transparent rotary panel perimetral face (22) and a rotary frame coupling face (23) facing said transparent rotary panel perimetral face (22), the transparent rotary panel (21) being fitted into the rotary frame (20);
characterized in that the transparent rotary panel (21) has a size larger than a cavity defined by said rotary frame coupling face (23) before the coupling thereof, and wherein once coupled the transparent rotary panel (21) is compressed by the rotary frame (20) and said rotary frame (20) is elastically pulled all around assuring a secure and leak-tight attachment without adhesives; and wherein
the coupling of the transparent rotary panel (21) in the rotary frame (20) is obtained by said transparent rotary panel (21) being cooled, causing it to shrink, and being inserted into the cavity defined by the rotary frame coupling face (23), being the rotary frame (20) heated causing it to expand, leaving a clearance between both which disappears when the transparent rotary panel (21) and the rotary frame (20) reach one and the same temperature.

2. The viewing hole according to claim 1, wherein the transparent rotary panel (21) is circular.

3. The viewing hole according to claim 2, wherein the transparent rotary panel perimetral face (22) and the rotary frame coupling face (23) are both cylindrical and concentric with said axis of rotation.

4. The rotary viewing hole according to claim 1, 2 or 3, wherein the transparent rotary panel perimetral face (22) and the rotary frame coupling face (23) are faces rectified to precise dimensions within established tolerances.

5. The rotary viewing hole according to any one of the preceding claims, wherein the rotary joint (40) is a labyrinth seal.

6. The rotary viewing hole according to any one of the preceding claims, wherein the intermediate chamber (1) contains a modified atmosphere, with positive pressure from inside to outside through the labyrinth seal, that has been supplied by a modified atmosphere supply device connected to said intermediate chamber (1).

7. A centrifugal machine including a fluid treatment chamber (51) and provided with a self-cleaning rotary viewing hole according to any one of preceding claims 1 to 6, wherein the stationary frame (10) of the rotary viewing hole is attached to a casing (50) of said fluid treatment chamber (51) by means of a leak-tight joint, so that the transparent rotary panel (21) is in contact with the inside of said fluid treatment chamber (51).

Ansprüche

1. Selbstreinigendes Drehsichtfenster für Zentrifugenmaschine umfassend:

- einen feststehenden Rahmen (10);

- eine transparente feststehende Scheibe (11), die mittels einer leckdichten Verbindung (41) an dem genannten feststehenden Rahmen angebracht ist;

- einen Drehrahmen (20), der durch eine Drehverbindung (40) mit dem genannten feststehenden Rahmen (10) verbunden ist;

- eine transparente Drehscheibe (21), die mittels einer Verbindung an dem genannten Drehrahmen (20) angebracht ist, wobei die genannte transparente Drehscheibe (21) gegenüber der transparenten feststehenden Scheibe (11) angeordnet und durch eine Zwischenkammer (1) von dieser getrennt ist;

- und einen Motor (30), der mit der genannten transparenten Drehscheibe (21) oder dem genannten Drehrahmen (20) verbunden ist, um deren Drehung relativ zu dem feststehenden Rahmen (10) um eine Drehachse senkrecht zu der genannten transparenten Drehscheibe (21) zu bewirken; wobei

die Verbindung zwischen der transparenten Drehscheibe (21) und dem Drehrahmen (20) eine Einpressverbindung (43) ist, die durch einen Maßpresssitz zwischen einer Perimeterfläche (22) der transparenten Drehscheibe und einer Kopplungsfläche (23) des Drehrahmens, die der genannten Perimeterfläche (22) der transparenten Drehscheibe zugewandt ist, entsteht, wobei die transparente Drehscheibe (21) in den Drehrahmen (20) eingepasst ist;
dadurch gekennzeichnet, dass
die transparente Drehscheibe (21) eine Größe aufweist, die größer ist als ein Hohlraum, der durch die genannte Kopplungsfläche (23) des Drehrahmens vor dem Zusammenfügen derselben definiert ist, und wobei die transparente Drehscheibe (21) nach dem Zusammenfügen durch den Drehrahmen (20) zusammengedrückt wird und der genannte Drehrahmen (20) allumfänglich elastisch gespannt wird, um eine sichere und leckdichte Befestigung ohne Klebstoffe zu gewährleisten; und wobei die Einkopplung der transparenten Drehscheibe (21) in den Drehrahmen (20) dadurch erzielt wird, dass die genannte transparente Drehscheibe (21) gekühlt wird, wodurch sie schrumpft und in den von der Kopplungsfläche (23) des Drehrahmens definierten Hohlraum eingepasst wird, wobei der Drehrahmen (20) erwärmt wird, wodurch er sich ausdehnt und zwischen den beiden ein Abstand entsteht, der sich aufhebt, wenn die transparente Drehscheibe (21) und der Drehrahmen (20) ein und dieselbe Temperatur erreichen.

2. Sichtfenster nach Anspruch 1, wobei die transparente Drehscheibe (21) kreisförmig ist.

3. Sichtfenster nach Anspruch 2, wobei sowohl die Perimeterfläche (22) der transparenten Drehscheibe als auch die Kopplungsfläche (23) des Drehrahmens zylindrisch und konzentrisch zur genannten Drehachse sind.

4. Drehsichtfenster nach Anspruch 1, 2 oder 3, wobei die Perimeterfläche (22) der transparenten Drehscheibe und die Kopplungsfläche (23) des Drehrahmens auf genaue Maße innerhalb festgelegter Toleranzen geschliffen sind.

5. Drehsichtfenster nach einem der vorstehenden Ansprüche, wobei die Drehverbindung (40) eine Labyrinthdichtung ist.

6. Drehsichtfenster nach einem der vorstehenden Ansprüche, wobei die Zwischenkammer (1) eine Schutzatmosphäre mit Überdruck von innen nach außen durch die Labyrinthdichtung enthält, die von einer mit der genannten Zwischenkammer (1) verbundenen Vorrichtung zur Zufuhr von Schutzatmosphäre zugeführt wurde.

7. Zentrifugenmaschine mit einer Fluidbehandlungskammer (51) und einem selbstreinigenden Drehsichtfenster nach einem der vorstehenden Ansprüche 1 bis 6, wobei der feststehende Rahmen (10) des Drehsichtfensters mittels einer leckdichten Verbindung an einem Gehäuse (50) der genannten Fluidbehandlungskammer (51) befestigt ist, so dass die transparente Drehscheibe (21) mit der Innenseite der genannten Fluidbehandlungskammer (51) in Kontakt ist.

Revendications

1. Un trou de regard rotatif autonettoyant pour une machine centrifugeuse comprenant :

- un cadre fixe (10) ;

- un panneau fixe transparent (11) fixé sur ce cadre fixe au moyen d'un joint étanche aux fuites (41) ;

- un cadre rotatif (20) relié à ce cadre fixe (10) au moyen d'un joint rotatif (40) ;

- un panneau rotatif transparent (21) fixé sur ce cadre rotatif (20) au moyen d'un joint, ce panneau rotatif transparent (21) étant disposé opposé et écarté du panneau fixe transparent (11) par une chambre intermédiaire (1) ; et

- un moteur (30) connecté à ce panneau rotatif transparent (21) ou à ce cadre rotatif (20) pour causer sa rotation par rapport au cadre fixe (10) autour d'un axe de rotation perpendiculaire à ce panneau rotatif transparent (21) ;

dans lequel
le joint entre le panneau rotatif transparent (21) et le cadre rotatif (20) est une attache de fixation (43) obtenue par un ajustement serré dimensionnel monté produit entre une face périmétrique (22) du panneau rotatif transparent et une face de couplage (23) du cadre rotatif faisant face à cette face périmétrique (22) du panneau rotatif transparent, le panneau rotatif transparent (21) étant ajusté dans le cadre rotatif (20) ;
caractérisé en ce que
le panneau rotatif transparent (21) a une taille plus grande qu'une cavité définie par cette face de couplage (23) de cadre rotatif avant son couplage et dans lequel, une fois couplé, le panneau rotatif (21) transparent est comprimé par le cadre rotatif (20) et ce cadre rotatif (20) est élastiquement tiré tout autour en assurant une attache sûre et étanche aux fuites sans adhésifs ; et dans lequel le couplage du panneau rotatif transparent (21) dans le cadre rotatif (20) est obtenu par le refroidissement de ce panneau rotatif transparent (21), qui le fait rétrécir, et étant inséré dans la cavité définie par la face de couplage (23) du cadre rotatif, le cadre rotatif (20) étant chauffé en le faisant s'étendre , en laissant un dégagement entre les deux qui disparaît lorsque le panneau rotatif transparent (21) et le cadre rotatif (20) arrivent à une et même température.

2. Le trou de regard conformément à la revendication 1, dans lequel le panneau rotatif transparent (21) est circulaire.

3. Le trou de regard conformément à la revendication 2, dans lequel la face périmétrique (22) du panneau rotatif transparent et la face de couplage (23) du cadre rotatif sont toutes les deux cylindriques et concentriques avec cet axe de rotation.

4. Le trou de regard rotatif conformément à la revendication 1, 2 ou 3, dans lequel la face périmétrique (22) du panneau rotatif transparent et la face de couplage (23) du cadre rotatif sont des faces rectifiées à des dimensions précises à l'intérieur de tolérances établies.

5. Le trou de regard rotatif conformément à une quelconque des revendications précédentes, dans lequel le joint rotatif (40) est un presse-garniture à labyrinthe.

6. Le trou de regard rotatif conformément à une quelconque des revendications précédentes, dans lequel la chambre intermédiaire (1) contient une atmosphère modifiée, ayant une pression positive de l'intérieur vers l'extérieur à travers le presse-garniture à labyrinthe, qui a été alimentée par un dispositif d'alimentation en atmosphère modifié connecté à cette chambre intermédiaire (1).

7. Une machine centrifugeuse comportant une chambre de traitement de fluide (51) et pourvue d'un trou de regard rotatif autonettoyant conformément à une quelconque des revendications précédentes 1 à 6, dans laquelle le cadre fixe (10) du trou de regard rotatif est attaché à un boîtier (50) de cette chambre de traitement de fluide (51) au moyen d'un joint étanche aux fuites de sorte que le panneau rotatif transparent (21) est en contact avec l'intérieur de cette chambre de traitement de fluide (51).

Drawing